I am just finishing Code Complete 2nd edition by Steve McConnell. This book should be a must read for any developer looking to improve the quality of thier code. Code Complete focuses on all aspects of software development from variable naming to integration testing.

Code Complete is a software development book, written by Steve McConnell and published by Microsoft Press, urging developers to get past code and fix programming and the "big design up front" waterfall model. It is also a compendium of useful software construction techniques, from naming variables to deciding when to write a subroutine.